Griffin Survivor Hybrid Case for iPhone 4 & 4S - Black Designed and independently tested to meet conditions outlined in US Department of Defense MIL-STD-810 Integral Display shield deflects wind and rain (Test: up to 200 mm/hr. for 1 hour) Rigid internal frame protects against shocks and drops (Test: drop on flat concrete surface from 6 ft./1.8 m) Sealed ports block blown sand and dust (Test: up to 18 m/sec for 1 hour) Silicone cladding absorbs vibration (Test: 18 hrs. at 20 to 2000 Hz)